Glazing batting materials



2,693,432 GLAZING'BATTING MATER ALS Fred Fortess, Summit; N. .J'ayassignor to Celanese, Corporation of America, New York; N; Y;, 'a' 'corporation of Delaware N a g-'1' Afip cat qi xl nu yffi, 1951,

, Serial No. 207,835

This invention relates toi the I glazing of batting materials and relates more particularly to'anirnproved process for the glazingof battingmaterials formed fromiorganic thermoplastic staple fibers. I

Batting materials formed from' organic thermoplastic staple fibers have found extensive use in a n'umber of fields. Batting materials-having a 'relatively substantial thickness are employed as structural insulation. ;-Ina much thinner form; the batting mater-ials serve aslinings and interlinings for: garments of various'types: 0ne difficulty experienced in the application of said' batting maganic thermoplastic staple fibers'to' coalesce with adjoining fibers, rendering the structure of the -battingmaterials more coherent. To avoid a serious loss in the insulating properties of the batting materials, efforts were made to control the heat treatment-so -as-to cause the fibers at the surface only of the batting materials to coalesce with adjoining fibers, which treatment is called glaz- 1 ing. However, when heat alone was employed'to; glaze the batting n1aterials,- the high temperature required rendered it difficult toprevent theco'alescen'ce' of staple fibers throughoutthe entire thickness of the batting materials and/or the degradation of the staple fibers at the surface of said materials. If, on the otherhand, the staple fibers were treated With aplasticizer' to permit said battingmater-ials to be glazed at a lower temperature, the major portion of the plasticizer; which was in the body of the batting materials, was wasted.

It is an important object of this invention to provide a process for the glazing of batting materials formed from organic thermoplastic staple fibers which will be free from the foregoing and other disadvantages.

A further object of this invention is to provide an improved process for the glazing of batting materials formed from organic thermoplastic staple fibers to produce a coherent structure, which may be carried out at a reduced temperature and which will produce a uniform coalescence of the staple fibers at the surface only of the batting materials without wasting any materials.

Other objects of this invention will be apparent from the following detailed description and claims.

I have now discovered that batting materials formed from organic thermoplastic staple fibers may be glazed uniformly at a reduced temperature to provide a strong, flexible, fused, porous surface and a strong coherent structure, if there is applied to the surface of the batting materials an aqueous solution or dispersion, hereinafter referred to generally as an aqueous solution, of a softening agent for the organic thermoplastic staple fibers having a boiling point above about 125 C., and the so-treated batting materials are then immediately subjected to the desired heat treatment as, for example, by subjecting the same to the action of a heated surface. The batting materials treated in accordance with this process exhibit a uniform coalescence of the staple fibers at the surface only so that they retain the major portion of their insulating properties. In addition, the structure of the batting materials is sufiiciently coherent to prevent their shred- United States PatefifO 2,693,432 Patented Nov. 2, 1954 iding and separating during the handling normally encountered in using the same.

i For the preparation of-the batting materials there may beemployed any standard carding machines having a Lbatting'attachment in combination therewith, as is well i pionate and cellulose acetate butyrate, and cellulose ethers "such as ethyl celluloseand benzyl cellulose. fibersmay also be formed from organic thermoplastic The staple materials as, for example, polyamides, polyurethanes, polytriazoles and vinyl polymers and copolymers. There may be mixed with the organic thermoplastic staple fibers staple fibers of materials that are not thermoplastic as,- for example,'cotton, silk, wool, regenerated 1 cellulose, jute, hemp and asbestos fibers.

In forming the batting -materials, the staple fibers are interlaced and 'matted together so that they exhibit some degree of co- .1 h'erence' even before the glazing operation.

In carrying out the process of this invention, there 1s applied to the surface of the batting materials an aqueous solution of a softening agent for the organic {thermoplasticmaterial having a boiling point above about 125 C. The softening agent may be a solvent, swelling agent or plasticizer for the organic thermoplastic material and maybe a high boiling liquid or solid. Suitable softening agents include, for' example, glycerol diacetate, glycol diacetate, dimethoxy tetraethylene glycol, diethylene glycol monoethyl ether, acetylacetone, triethylphosphate,

ethyl lactate, diethyle'ne glycol, urea,-acetamide, potassium thiocyanate and boric acid. The softening agent must, as pointed out above, have a boiling point above about 125 C. since it has been foundthat softening agents having a lower boiling point are largely flashed off and therefore do not 'efficiently effect the glazing of the batting materials to provide a strong, flexible, fused, porous surface. The aqueous solution of the softening agent advantageously has a concentration of between about Sand 20% by weight and is applied to the batting materials in amount sufilcient to deposit from about 0.025 1 to 0.4 ounce of softening agent for each square yard of surface of =-the batting materials being treated. The

aqueous solution of the softening agent may be applied w to one or-both surfaces of the batting materials and may -be readily 'sprayedonto said surfaces through the use of suitable nozzles. Through theiapplication of the softening agents in the form of aqueous solutions, it

is possible to apply "solid as well as liquid softening agents and to distribute the softening agents uniformly over the surface of the batting materials despite the small quantities of said agents that are employed. Certain of the softening agents, such as urea, boric acid and triethylphosphate have fire-retardant properties and will provide a fire-retardant surface on the batting materials in addition to assisting the glazing operation.

The batting materials are subjected to the action of a heated surface immediately after the aqueous solution of the softening agent is applied to the surface of said batting materials, and before said solution has an opportunity to diffuse into the interior of said batting materials. In this way, the coalescence of the organic thermoplastic staple fibers in the interior of said batting materials is substantially avoided. The temperature of the heated surface is advantageously maintained between and 150 C. when glazing batting materials formed from staple fibers having a basis of cellulose acetate, and said 'heated surface is applied to the batting materials for a period of time sufficient to bring the temperature at the surface of the batting materials to between about 110 and C. Suitable apparatus that may be employed in applying a heated surface to the batting material include presses, calender rolls and the like.

The following examples are given to illustrate this invention further.

Example I A batting material formed from interlaced and matted cellulose acetate staple fibers and having a thickness of between and /2 inches is sprayed on one surface with a by weight aqueous solution of glycol diacetate in an amount sufficient to deposit 0.2 ounce of the glycol diacetate on each square yard of the batting surface. 1mmediately after the spraying is completed, the batting is contacted for 3 seconds and under a pressure of 2 pounds per square inch with a heating element maintained at 132138 C. Upon removing the heating element, it is found that the batting is glazed uniformly at its surface only, exhibits a strong, flexible, fused, porous surface and has a firm coherent structure.

Example 11 The process described in Example I is repeated employing a 10% by weight of a warm solution of boric acid and depositing 0.2 ounce of boric acid per square yard of batting surface. The batting is glazed uniformly at its surface only, exhibits a strong flexible, fused, porous surface and has a firm coherent structure.

Example III The process described in Example I is repeated employing a 10% by weight solution of urea and depositing 0.2 ounce of urea per square yard of batting surface. The batting is glazed uniformly at its surface only, exhibits a strong, flexible, fused, porous surface and has a firm coherent structure.

Example IV The process described in Example I is repeated employing a 10% by weight solution of acetarnide and depositing 0.2 ounce of acetamide per square yard of batting surface. The batting is glazed uniformly at its surface only, exhibits a strong, flexible, fused, porous surface and has a firm coherent structure.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patent is:

1. Process for the glazing of batting materials formed from organic derivative of cellulose staple fibers interlaced and matted together, which comprises applying to the surface of the batting materials an aqueous solution of a normally solid softening agent for the organic derivative of cellulose material, in an amount sufficient to deposit from about 0.025 to 0.4 ounce of softening agent per square yard of the surface of the batting materials, and subjecting the batting materials to the action of a heated surface whereby the organic derivative of cellulose staple fibers are coalesced at the surface only of the batting materials.

2. Process in accordance with claim 1 wherein the normally solid softening agent for the organic derivative of cellulose material is urea.

3. Process in accordance with claim 1 wherein the normally-solid softening agent for the organic derivative of cellulose material is boric acid.

4. Process in accordance with claim 1 wherein the normally solid softening agent for the organic derivative of cellulose material is acetamide.

5. Process for the glazing of batting materials formed from cellulose acetate staple fibers interlaced and matted together, which comprises applying to the surface of the batting materials an aqueous solution of a normally solid softening agent for the cellulose acetate material, in an amount sufficient to deposit from about 0.025 to 0.4 ounce of softening agent per square yard of the surface of the batting materials, and subjecting the batting materials to the action of a heated surface whereby the cellulose acetate staple fibers are coalesced at the surface of the batting materials.

6. Process for the glazing of batting materials formed from cellulose acetate staple fibers interlaced and matted together, which comprises applying to the surface of the batting materials a 5 to 20% by weight aqueous solution of a normally solid softening agent for cellulose acetate material in an amount sufficient to deposit from about 0.025 to 0.4 ounce of softening agent per square yard of the surface of the batting materials, and, without permitting the aqueous solution to diffuse into the interior of the batting materials, subjecting the batting materials to the action of a heated surface having a temperature of between about and C. whereby the cellulose acetate staple fibers are coalesced at the surface only of the batting materials.

7. Process in accordance with claim 5 wherein the normally solid softening agent for the cellulose acetate material is urea.

8. Process in accordance with claim 5 wherein the normally solid softening agent for the cellulose acetate material is boric acid.

9. Process in accordance with claim 5 wherein the normally solid softening agent for the cellulose acetate material is acetamide.

References Cited in the file of this patent UNITED STATES PATENTS 

1. PROCESS FOR THE GLAZING OF BATTING MATERIALS FORMED FROM ORGANIC DERIVATIVE OF CELLULOSE STAPLE FIBERS INTERLACED AND MATTED TOGETHER, WHICH COMPRISES APPLYING TO THE SURFACE OF THE BATTING MATERIALS AN AQUEOUS SOLUTION OF A NORMALLY SOLID SOFTENING AGENT FOR THE ORGANIC DERIVATIVE OF CELLULOSE MATERIAL, IN AN AMOUNT SUFFICIENT TO DEPOSIT FROM ABOUT 0.025 TO 0.4 OUNCE OF SOFTENING AGENT PER SQUARE YARD OF THE SURFACE OF THE BATTING MATERIALS, AND SUBJECTING THE BATTING MATERIALS TO THE ACTION OF A HEATED SURFACE WHEREBY THE ORGANIC DERIVATIVE OF CELLULOSE STAPLE FIBERS ARE COALESCED AT THE SURFACE ONLY OF THE BATTING MATERIALS.
 2. PROCESS IN ACCORDANCE WITH CLAIM 1 WHEREIN THE NORMALLY SOLID SOFTENING AGENT FOR THE ORGANIC DERIVATIVE OF CELLULOSE MATERIAL IS UREA. 